Find the Unit Tangent Vector $\mathrm { T } ( t ) \text { for the line tangent to the space curve }$

Multiple Choice

Find the unit tangent vector
$\mathrm { T } ( t ) \text { for the line tangent to the space curve }$ $\mathbf { r } ( t ) = \langle 12 \cos t , 12 \sin t , 3 )$ at point $p ( 6 \sqrt { 2 } , 6 \sqrt { 2 } , 3 )$ .

A) $\mathbf { T } \left( \frac { \pi } { 4 } \right) = \frac { 1 } { 4 } ( - \sqrt { 2 } , - \sqrt { 2 } , 3 )$
B) $\mathrm { T } \left( \frac { \pi } { 4 } \right) = \frac { 1 } { 4 } ( - \sqrt { 2 } , \sqrt { 2 } , 0 )$
C) $\mathrm { T } \left( \frac { \pi } { 4 } \right) = \frac { 1 } { 2 } ( \sqrt { 2 } , - \sqrt { 2 } , 3 )$
D) $\mathrm { T } \left( \frac { \pi } { 4 } \right) = \frac { 1 } { 2 } ( - \sqrt { 2 } , \sqrt { 2 } , 0 )$
E) $\mathrm { T } \left( \frac { \pi } { 4 } \right) = \frac { 1 } { 2 } ( \sqrt { 2 } , - \sqrt { 2 } , 0 )$